Bain Capital and Thomas H Lee, two US private equity groups, have re-entered the race to buy Warner Chilcott after joining a consortium of rival firms that has had its £1.62bn bid for the Northern Irish drugs firm recommended.

The consortium they are joining, Waren Acquisition, is advised by Credit Suisse First Boston and comprises DLJ Merchant Banking Partners, CSFB's private equity arm, and JP Morgan Partners, the private equity arm of the US bank.